Cobblemon: Rocket Balls

I originally made this mod for myself to use in singleplayer. Later, I started playing with a friend on a server and continued developing it for our game.

This is a vibe-coded project made just for fun. I enjoyed playing with it, so I wanted to share it with others.

The inspiration came from Pokémon ROM hacks i played such as Rocket Edition and Bloody Platinum, and the idea of stealing from other Trainers.

Three tiers of Rocket Balls

All three tiers use a Slate Ball-inspired design with a red R. Their center buttons make them easy to tell apart.

Tier I — Rocket Ball

The basic Rocket Ball has a silver button and a 1× capture multiplier, like a regular Poké Ball.

Craft it with Apricorns, iron ingots and a Diamond. The recipe produces one Rocket Ball.

Tier II — Rocket Ball

Tier II has a gold button and a 5× capture multiplier.

Craft it with Apricorns, iron ingots and a Nether Star.

Tier III — Master Rocket Ball

The Master Rocket Ball has a diamond-blue button and uses a guaranteed capture calculation, like a Master Ball.

Craft it with Apricorns, iron ingots and a Dragon Egg. Yes the Dragon Egg!! we didnt had a use for it and this makes it possible to craft only 1 on a Server.

This is also the only tier that can permanently steal another player’s Pokémon during a PvP battle.

The 1× and 5× multipliers modify Cobblemon’s normal capture calculation; they are not fixed success percentages. The Master tier still requires a valid target and a successful storage transfer.

How to capture trainer Pokémon

1. Start a battle against an RCT NPC trainer.

2. Weaken the opposing Pokémon to improve your chances with Tier I or II.

3. During your own action-selection turn, throw a Rocket Ball at the trainer’s active Pokémon.

4. If the capture succeeds, you receive the Pokémon in your party or PC, and the battle ends as your victory.

For NPC battles, you receive a permanent copy. The trainer keeps its original team for future battles.

If the capture fails, the ball is consumed and the battle continues.

Stealing Pokémon in PvP

Player theft is permanent. Server owners should make sure their players know this before installing the mod. (or create some Drama and dont tell them 😀 )

Only the Master Rocket Ball — Tier III can steal player-owned Pokémon, and only from an active opponent in your own ongoing PvP battle.

On a successful capture:

• The original Pokémon is removed from the defender’s party.
• It moves to the catcher’s party or PC.
• Its Pokémon ID and original-trainer history are preserved.
• The battle ends as the catcher’s victory.

The defender does not keep a copy. Tier I and II cannot steal Player Pokémon, and you cannot use this mechanic outside your own active PvP battle.

The transfer checks ownership, the ongoing battle, player connections and available storage before completing. If it cannot complete, the Pokémon stays with its owner.

Permanent PvP theft currently has no separate configuration toggle or built-in undo command.

Requirements

• Minecraft: 1.21.1
• Mod loader: Fabric
• Java: 21
• Fabric Loader: 0.18.0 or newer
• Cobblemon: 1.8.4
• Radical Cobblemon Trainers API: 0.16.2-beta
• Radical Cobblemon Trainers: 0.19.2-beta
• Fabric API
• The normal dependencies required by Cobblemon and RCT, including Architectury API and Forge Config API Port

Testing and feedback

This is a small, experimental project. NPC captures and the visual features have been confirmed in playtests. Permanent PvP transfers and several failure cases have been checked with automated tests using simulated server players.

A complete real-time PvP capture with two connected Minecraft clients has not yet been confirmed. Please back up your world before testing permanent theft. (We arent yet in the End and my Mate wont test it with me….yet 😀 )

If you find a bug, leave a comment and what happened.

Future Ideas:

• More Team Balls: New balls inspired by Team Magma, Team Aqua, Team Plasma, Team Galactic, and Rainbow Rocket, with unique designs and capture bonuses.

• Capture Protection: Protect your Pokémon from theft with special held items.
• Configuration Options: Adjust capture multipliers and enable or disable Pokémon theft in PvP battles.
• Maybe NeoForge Support: so more players can use the mod with their preferred modpacks.
• Throwing Particles: Unique particle effects for each team’s balls.

• Impact & Capture Effects: Unique team-themed particle effects when a ball hits its target and during the capture animation

• Capture Bonus Tooltips: Item tooltips showing capture multipliers and their conditions.
• Advancements: Unlock advancements for capturing trainer Pokémon and collecting Team Balls.
• Theft Log: A server log recording who stole which Pokémon and from whom.

Credits

Created by Varomos with AI-assisted development.

The Slate Ball texture foundations and original ball model come from Cobblemon and its asset contributors. Cobblemon-derived assets retain their separate CC BY-NC 3.0 license, with modifications for the red R and tier-specific buttons.

This is an independent addon and is not affiliated with or endorsed by the Cobblemon team, RCT developers, Mojang, Microsoft, Nintendo, Game Freak or The Pokémon Company.